The invention relates to vehicles, and to methods of controlling inter-vehicle gap(s) between a lead vehicle and one or more following vehicles. The invention also relates to a computer program, a computer readable medium, and a control unit. The invention can for example be applied in heavy-duty vehicles, such as trucks and buses.
Inter-vehicle gap may be controlled using radar-based adaptive cruise control (ACC) that keeps a safe distance to the vehicle in from by controlling the accelerator and brakes.
Cooperative adaptive cruise control (CACC) is an extension of ACC. In CACC, information may be sent from the vehicle ahead to the following vehicle using vehicle to vehicle communications, which information may be used by the following vehicle to even better keep the aforementioned safe distance to the vehicle ahead.
It is desirable to provide an improved method of controlling inter-vehicle gap(s).
According to the first aspect, there is provided a vehicle configured to perform the steps of: obtaining an indicator of a potential collision threat identified by an autonomous emergency braking system of the vehicle, wherein the autonomous emergency braking system of the vehicle comprises pre-defined control phases, and wherein the indicator at least partly determines a current control phase of the autonomous emergency braking system; and sending the obtained indicator to one or more following vehicles. The vehicle may be referred to as a lead vehicle.
The pre-defined control phases of the autonomous emergency braking system may for example be standardized or statutory. The present invention is based on the understanding that by sending said indicator obtained from the (lead) vehicle's autonomous emergency braking system to the following vehicle(s), the following vehicle(s) can due to the pre-defined control phases of the autonomous emergency braking system predict what the lead vehicle will do and take appropriate pre-emptive action.
The indicator may be time to collision (TTC). Other indicators could be relative speed between the potential collision threat and the lead vehicle, distance between the potential collision threat and the lead vehicle, etc.
According to the second aspect, there is provided a method of controlling inter-vehicle gap(s) between a lead vehicle and one or more following vehicles, wherein the method comprises the steps of: obtaining an indicator of a potential collision threat identified by an autonomous emergency braking system of the lead vehicle, wherein the autonomous emergency braking system of the lead vehicle comprises pre-defined control phases, and wherein the indicator at least partly determines a current control phase of the autonomous emergency braking system; and sending the obtained indicator to the one or more following vehicles. This aspect may exhibit the same or similar features and/or technical effects as the first aspect of the invention, and vice versa.
The method may further comprise: receiving, in the one or more following vehicles, said indicator; and automatically adjusting the inter-vehicle gap(s) based on the received indicator.
The indicator may be time to collision.
Sending the indicator may be performed using vehicle-to-vehicle communication means.
Receiving the indicator may also be performed using vehicle-to-vehicle communication means.
The method may further comprise: obtaining, in the one or more following vehicles, a reading from one or more on-board sensors that measure the actual gap to a vehicle ahead; and automatically adjusting the inter-vehicle gap(s) based on the obtained reading. By automatically adjusting the inter-vehicle gap(s) based on the aforementioned received indicator and the obtained reading, a refined cooperative adaptive cruise control system may be realized.
The one or more on-board sensors may include at least one radar or at least one LIDAR device or at least one camera.
The received indicator may override the obtained reading in case the received indicator indicates a greater deceleration (of the following vehicle(s)) than the obtained reading, whereas the obtained reading may override the received indicator in case the obtained reading indicates a greater deceleration (of the following vehicle(s)) than the received indicator.
According to the third aspect of the invention, there is provided a vehicle configured to perform the steps of: receiving, in the vehicle, an indicator of a potential collision threat identified by an autonomous emergency braking system of a lead vehicle, wherein the autonomous emergency braking system of the lead vehicle comprises predefined control phases, and wherein the indicator at least partly determines a current control phase of the autonomous emergency braking system; and automatically adjusting an inter-vehicle gap based on the received indicator. This aspect may exhibit the same or similar features and/or technical effects as the previous aspects of the invention, and vice versa.
The indicator may be time to collision.
The vehicle may be referred to as a following vehicle.
According to the fourth aspect, there is provided a method of controlling inter-vehicle gap(s) between a lead vehicle and one or more following vehicles, wherein the method comprises the steps of: receiving, in the one or more following vehicles, an indicator of a potential collision threat identified by an autonomous emergency braking system of the lead vehicle, wherein the autonomous emergency braking system of the lead vehicle comprises pre-defined control phases, and wherein the indicator at least partly determines a current control phase of the autonomous emergency braking system; and automatically adjusting the inter-vehicle gap(s) based on the received indicator. This aspect may exhibit the same or similar features and/or technical effects as the previous aspects of the invention, and vice versa.
The indicator may be time to collision.
The method may further comprise: obtaining, in the one or more following vehicles, a reading from one or more on-board sensors that measure the actual gap to a vehicle ahead; and automatically adjusting the inter-vehicle gap(s) based on the obtained reading.
The one or more on-board sensors may include at least one radar or at least one LIDAR device or at least one camera.
The received indicator may override the obtained reading in case the received indicator indicates a greater deceleration than the Obtained reading, whereas the obtained reading may override the received indicator in case the obtained reading indicates a greater deceleration than the received indicator.
The invention also relates to a computer program comprising program code means for performing steps of the second or fourth aspect of the invention when said program is run on a computer.
The invention also relates to a computer readable medium carrying a computer program comprising program code means for performing steps of the second or fourth aspect of the invention when said program product is run on a computer.
The invention also relates to a control unit configured to perform steps of the second or fourth aspect of the invention. The control unit may for example be included in the lead vehicle and/or the following vehicle.
Further advantages and advantageous features of the invention are disclosed in the following description and in the dependent claims.